Optical disc has advantages of a large storage capability, easily preservation and maintenance, a long shelf period, low cost, and excellent data protection. It is increasingly used to substitute for conventional magnetic storage medium and thus becomes a popular optical storage medium for people not only in business but also in daily life. In general, various disc loading mechanisms for optical storage apparatus have been developed such as a single-disc tray and a multi-disc magazine. Regarding the multi-disc optical storage apparatus, it is necessary to use a multi-disc magazine for allowing an optical pickup unit to select-and read the disc appointed by user. Such multi-disc magazine is also found in some home video and audio equipments. Since such multi-disc magazine can carry plural of discs at one time, it can play and read discs sequentially for a long period without replacing new ones. Thus such multi-disc magazine design has also found in car-use audio equipment for drivers to enjoy their favorite music.
As above-mentioned, such a multi-disc optical storage apparatus capable of carrying plural of discs at one time generally equips with a multi-disc magazine to accommodate the discs. In the multi-disc magazine, there are plural of trays for holding each disc. However, according to a user's habit, not all trays of the magazine carry discs. Generally, the conventional multi-disc optical storage apparatus will first perform a complete disc detecting process while it is turned on. FIG. 1 shows a flow chart for a disc detecting process found in current multi-disc optical storage apparatus. As shown in FIG. 1, when a multi-disc optical storage apparatus is turned on or a multi-disc magazine is inserted in the apparatus (e.g. Step S110), the multi-disc optical storage apparatus performs a complete disc detecting process (e.g. Step S112), then the multi-disc optical storage apparatus is standby to perform the next action requested by user (e.g. Step S114). In current multi-disc optical storage apparatus, it detects the disc-carrying status in the multi-disc magazine through the complete disc detecting process and records the detected result in the memory of the storage apparatus for providing a reference to subsequently access the discs carried in the magazine.
FIG. 2 shows a flow chart for a complete disc detecting process found in current multi-disc optical storage apparatus. As shown in FIG. 2, the apparatus starts the complete disc detecting process (e.g. Step S210) to select a tray which has not yet been detected (e.g. Step S212) and then detect whether the detected tray has carried a disc (e.g. Step S214). If the detected tray carries a disc, the process is going to the Step S216 to read the information on the disc and then going to the Step S218 to determine whether all trays have already been detected. In Step S214, if the detected tray does not carry a disc, the process is going to the Step S218 to determine whether all trays have already been detected. In Step S218, if it determines that all trays have already been detected, the process is going to the Step S220 to show that the disc detecting process is completed. If it determines that not all trays have been detected, the process returns to the Step S212 to continue detecting the remaining tray which has not yet been detected. Thereby, the multi-disc optical storage apparatus will automatically omit the disc reading procedure on the tray if that carries no disc during the subsequent playing. Therefore, the time either for repetitive accessing or detecting empty tray is saved.
However, since the complete disc detecting process performs when the multi-disc optical storage apparatus is turned on or the multi-disc magazine is inserted in the apparatus, user should take time to wait for the completion of the disc detecting process. If all trays in the magazine have carried disc, it seems not necessary to perform such a complete disc detecting process to detect whether each tray has already carried a disc. In this regard, the complete disc detecting time is wasted for a user when the multi-disc optical storage apparatus is turned on or the multi-disc magazine is inserted in the apparatus.